The files open up at the most awkward moment for the black king.
21... f8g7  22. e7e5 Centralizing the queen with a tempo is the human choice. 22... g7g8 A dreadful move $1 The king cuts the communication between the rooks, and this is all White needs to organize his heavy pieces with decisive effect. 23. d6d7  23... a8d8 